Automatic parachute harness release assembly

ABSTRACT

An automatic releasing mechanism for parachute harnesses which employs water-actuatable cells to provide thermal energy to burn through harness control straps and to operate a pneumatic release mechanism to automatically open the harness buckles to free a wearer therefrom upon a water landing. A manual release is also provided to activate the pneumatic release mechanism to open the harness buckles after a landing on firm terrain.

United States Patent [72] inventors George M. Brown St. Petersburg; Phyllis L. Newman, Miami, both of Fla. [21] Appl. No. 46,745 [22] Filed June 16, 1970 [45] Patented Jan. 4, 1972 [73] Assignee Sauna International Inc.

Miami, Fla.

[54] AUTOMATIC PARACHUTE HARNESS RELEASE ASSEMBLY 30 Claims, 15 Drawing Figs.

[52] U.S.Cl 244/151, 24/73 [51] Int. Cl B64d 17/30 [50] Field 01 Search 244/ l 5 1;

[56] References Cited UNITED STATES PATENTS 3,023,498 3/1962 Temple et a1. 244/ 151 X 3,246,801 4/1966 DeBoer 9/325 X 3,404,439 10/1968 Jones et a1. 244/151 X Primary Examiner-Milton Buchler Assistant ExaminerCarl A. Rutledge Attorney-Fidelman, Wolfi'e & Leitner ABSTRACT: An automatic releasing mechanism for parachute harnesses which employs water-actuatable cells to provide thennal energy to burn through harness control straps and to operate a pneumatic release mechanism to automatically open the harness buckles to free a wearer therefrom upon a water landing. A manual release is also provided to activate the pneumatic release mechanism to open the harness buckles after a landing on firm terrain.

minnow 4m: 3.632.066

SHEET 2 OF 7 INVENTOB GEORGE M. BROWN PHYLLIS L. NEWMAN ATTORNEYS PAIENTEB 4 SHEET 3 [1F 7 mm mm mm mv Om INVENTOR GEORGE M. BROWN PHYLLIS L. NEWMAN ATTORNEYS mamam 4m 3632.066

SHEET s 0F 7 INVENTOR GEORGE M. BROWN PHYLLIS L. NEWMAN ATTORNEYS PATENTEU JAN 4 1872 SHEET 5 [1F 7 INVENTOR GEORGE M. BROWN PHYLLIS L, NEWMAN M ,4 44 X51210 ATTORNEYS PATENTEDJAN 4m 36321066 SHEET 8 OF I 7 K FIG 11 INVENTOR. GEORGE M BROWN BY PHYLLIS L. NEWMAN ATTORNEY manna-m 4m 3.632.066

sum 7 OF 7 INVENTOR. GEORGE M. BROWN PHYLLIS L. NEWMAN wll iefl wi ,4 TTORNEY AUTOMATIC PARACHUTE HARNESS RELEASE ASSEMBLY This invention relates to parachutes and like structures and particularly to automatic release mechanisms for the harness portions thereof. Specifically this invention relates to wateractuatable releases which, when submerged, provide severing action for harness belts whereby a parachutist is automatically released from his harness structure upon a water landing.

The parachute has brought with it obvious advantages and a number of problems to the wearer among which the difficulty of extraction therefrom after landing is paramount. This liability is increased when the landing is in water, the canopy tending at times to either completely encase the exposed portions of the chutist or alternatively act to drag him by wind still caught in the canopy. If the chutist has been injured or is unconscious, these problems are compounded to the point where an otherwise safe landing may terminate in the drowning of the chutist.

Automatically inflating life jackets, of course, substantially decrease the incidence of accidental drowning but still do not solve the problem of drag or envelopment by the chute. Obviously these latter situations could be rectified by automatic release mechanisms for the harness support but to date no satisfactory device has been designed therefor. The failure of such development appears to be based on the theory that automatic harness release should be accomplished at the buckles, and other standard release mechanism. This has resulted in cumbersome devices which have not performed satisfactorily for both the release and buckling requirements. Here we have a situation where the requirements of the buckle are incompatible with the criteria of the automatic escape mechanism, the former having high-strength, weathering, and locking characteristics, the latter only requiring automatic web severing.

This invention provides water actuatable cells for (1) automatically severing the control webs from the harness and (2) automatically operating a pneumatically control system to open the harness buckles to separate the parachutist from his harness. The water actuatable cells may be set up to perform either of the above two functions only. Using them to both sever the control webs from the harness and to activate the pneumatic assembly to open the harness buckles provides an additional margin of safety. The system also employs a manually operated plunger system to activate the pneumatic system to open the harness buckles. The latter feature is used when the parachutist finds himself on land.

Therefore, it is a principal object of the instant invention to provide a release mechanism that automatically severs a control web or harness web upon water immersion.

It is a further object to provide an automatic release mechanism which is self contained and is separate from conventional canopy and harness release.

It is still a further object to provide a release mechanism which is water actuated, but can withstand all environmental conditions without accidentally operating.

It is a further object to provide an automatic release mechanism which can sever the control webs upon immersion of the chutist in the water and also automatically cause release of the body harness buckles.

It is a further object to provide a self contained pneumatic release assembly for releasing harness buckles which is either automatically operable upon water immersion or which can be manually activated by the chutist.

FIG. 1 shows a chutist wearing a parachute harness illustrating the locations of the embodiments of the present invention.

FIG. 2 shows the automatic harness release mechanism in place on a main harness strap.

FIG. 3 shows a bottom view of the mechanism and harness strap of FIG. 2.

FIG. 4 is a similar view to FIG. 3 showing the harness strap in separated condition.

FIG. 5 is a front view of the automatic harness release mechanism showing portions in section.

FIG. 6 is a front view of the automatic harness release mechanism similar to FIG. 5 showing the device being actuated.

FIG. 7 shows the automatic harness strap release mechanism connected to a manual pneumatic release mechanism.

FIG. 8 shows a large top view of the firing pin slide.

FIG. 9 shows a top sectional view of the female harness buckle having a manual release and provisions for the single point automatic release mechanism to actuate the buckle.

FIG. 10 is a view taken along line 10-10 of FIG. 9.

FIG. 11 is a sectional view of the actuating piston for automatic release of the female buckle latching pivot.

FIG. 12 is a perspective view of the latching pivot.

FIG. 13 is a view showing the male portion of the harness buckle.

FIG. 14 is an exploded view of the manual buckle release mechanism with its biasing spring and pivot pin.

FIG. 15 is a view showing the female portion of the harness buckle.

Referencing now to FIG. 1 there is shown a parachutist 1 wearing an aviation suit 2 and an oxygen and communications helmet 3. The chutist is wearing a harness 4 of conventional configuration with shoulder, leg and chest straps. Mounted on the harness are release buckles 4, 5, 6, 7 and 8. Attached through buckles 8 and 13 to the harness are main chute control straps 10 and 11 which are, in turn, connected to shroud lines as at 12.

Mounted on control straps are automatic strap release mechanisms 13 and 14. FIG. 2 shows such a mechanism designated generally as 20. It consists of a substantially rectangular case 21 having strap engaging portions 22 and 23 which have slots 24 and 25 through which passes the strap 1 1.

An attachment plate 26 is mounted on the strap on the side opposite the case 21 by screws 27, 28 which pass through plate 26 and the control strap 11.

On opposite ends of the case 21 are water pressure activated chambers 29 and 30. Between the chambers is a activation cell chamber 31 containing a magnesium-silver chloride cell 32. A cover plate 33 maintains the cell within the chamber and is secured on case 21 by screws 34.

Within each end portion is a cylindrical chamber 35. One end of the chamber is internally threaded as at 36 to receive a threaded plug 37. The opposite end of chamber 35 is counterbored as at 38 to receive a ventilated valve cover 39 with a series of small holes 40 to allow water to enter the chamber. Chamber 35 is annularly relieved as at 41 and 41 is in communication with a passage 42 which, in turn, is in communication with chamber 31 and cell 32.

A cylindrical valve member 43 is mounted for sliding movement within chamber 35. Both valve 43 and plug 37 are internally bored as at 44 and 50 and receive a compression spring 53 therebetween. Valve member 43 is annularly relieved as at 46 and accommodates an annular O-ring seal 47. Seal 47 engages the flared part of relieved portion 41 and is kept there by the action of the spring 53. Plug 37 is similarly relieved as at 51 to receive a second sealing O-ring 52. The face of plug 37 has a hexagonal hole by which the plug can be engaged by a wrench to turn it to either adjust the tension of spring 53 as to disassemble the device.

Cell 32 has an insulating plug 55 and wires 56 leading therefrom. As shown in FIG. 2 the wires 56 are shown in contact with the cell 32. An insulating plate 57 is secured between case 21 and control strap 1 1. The wires 56 are sewn across the strap in a fashion as shown in FIG. 3. While the design shown is preferred other designs, most of the conventional in sewing or stitching, can be employed such as series, parallel, etc. The only limitation on the design would be the wires themselves. The preferred wire is made of Microchromate. It is like Nichrome wire which gets red hot upon a current passing through it.

FIG. 7 shows a water pressure activated harness release mechanism 20' employed in conjunction with a gas operated buckle release mechanism 70. Mechanism 20' operates in the same manner and is of the same construction as mechanism 20. The essential difference is in the use of the wires to connect the cell through two Joule condenser 1 capacitors (60) to an electric solenoid 72.

Mechanism 70 comprises a housing having a chamber 71 in which the electric solenoid 72 (not shown in detail) is housed. The solenoid 72 is adapted to thrust a rod 72.

The lower part of housing 70 has a threaded bore 73 which receives a C cartridge 75 having a threaded neck 74. Above neck 74 is an elongated passageway 76 which connects with a gas escape passage 77 by a port 78. Coaxial with passageway 76 is a smaller diameter passage 79.

A slot 80 connects chamber 71 with a cut out area 81 on the comer of housing 70.

Mounted for sliding movement within passageway 76 is a firing pin 83 having a notched portion 84, a pointed piercing portion 86 and a hole 85 connecting portions 84 and 86. Hole 85 allows the gas to enter portion 84 and then chamber 77 after the cartridge is punctured. Pin 83 has a reduced neck portion 87 and a head portion 88. A compression spring 89 biases the pin downwardly.

Positioned within slot 80 is firing pin actuating slide 90. FIG. 8 shows the slide and its position relative to portion 87 and head 88 of pin 83 when the mechanism is ready to be used but before firing. Slide 90 has a large cutout 92 in communication with a narrow slot 91. When the slide is shoved to the left, as viewed in FIG. 8, allows spring 89 to thrust pin 83 into cartridge 75.

Mounted in cutout area 81 is a manual operating lever 95 with a pull lanyard 97 attached thereto through a hole 96. Lever 95 is pivoted about pin 98 and has a tapered slide engaging lip 94 which passes through the end of slide slot 91 and into a curved cutout area 82. When the lever 95 is pulled outwardly and pivots around 98 and pulls slide 90 to allow pin to puncture cartridge 75 The gas escapes through passage 77 to nylon tubing (sewn into the webbing of the harness straps, not shown) and to a female buckle portion 100.

Buckle portion 100 is similar to the buckles shown and described in a copending application, Ser. No. 763,249, filed Sept. 27, 1968, by this applicant entitled RELEASEABLE COUPLING. The contents of the patent application, Ser. No. 763,249, are hereby incorporated into this application by reference.

Portion 100, shown in FIGS. 9 and 10, consists of a housing 101, generally rectangular in shape. It has a lower surface 102 which is surrounded by raised housing 101 having curved wall portion 103, straight wall portion 104, curved wall portion 105 of a larger radius than portion 103 and ending in straight wall portion 106. A latch 105 is surrounded by these walls and is adapted to pivot in the direction shown by the arrow in FIG. 9 about a pivot cam 133. Latch 105 has a cylindrical aperture 106 which has a raised portion 108.

Extending from housing 101 are two arms 109, 111 which have holes 110, 112 which are adapted to receive a coupling strap fastener bar.

A pushbutton release 113 is located within aperture 106. Latch 105 has a cylindrical bore 120 which communicates with an open area 124. Area 124 has a large width section and a narrow width section. At the end of the narrow section in the surface 102 is a bore 126. A second bore 127 is located in surface 102. There is a cylindrical bore 150 in latch 105 and an arcuate area 151 is cut out adjacent bore 150. Area 105, however, has a ledge 151 which is above the surface 102.

Pushbutton release 1 13 (see FIG. 14) has a widened portion 114 extending therefrom which has an aperture 1 18 therethrough. A narrow section 115 is an extension of portion 114 and has a generally cylindrically shaped portion 116 extending downwardly therefrom at an angle of approximately The lower cylindrical projection 1 17 is adapted to engage bores 126 and 127. Pin 119 secures release 113 to latch 105 by its reduced portion passing through small-diameter bore 121 into cutout area 123. A ring 122 passes through a small hole in the end of pin 119. Located within area 123 is a piston assembly 155. Tubing 156 connects with piston assembly and is adapted to carry gas from the cartridge in mechanism 70.

Housing 101 has a slotted area 140 adapted to receive the male buckling portion. The slotted area defines a lip 129. Both lip 129 and the housing 101 have bores 130, 131 and latch has a square hole 132. A pivot cam 133 (FIG. 12) is received within hole 132 and bores and 131. Pivot 133 has a cylindrical portion 134 which received within hole 132, a cylindrical reduced portion 135, a larger diameter portion 137, and a slightly larger flange portion 139. Portion 137 has a slot 138 which forms a semicircle. A cam-actuating arm 154 extends out from section and is adapted to be actuated to swing approximately 20 through cut out area 170 (FIG. 9) to turn the cam pivot to allow the male buckle portion and female buckle portion to unlock.

FIG. 13 shows the general relationship of female buckle section 100 and male buckle section 200. Like section 100, section 200 has two arms 206, 20'! extending therefrom which have aligned holes 208, 209 therein. The main body section 210 has a projection 201 extending therefrom and is of a general parallelogram configuration with the exception of a notch in one side thereof. The sides 203 and 203' are approximately at 30 to the direction of coupling.

The edge 205 of the notch is at an additional 30 to the coupling direction and edge 204 is at 45 to the lateral dimension of portion 200.

Portion 100 has a similar shape in cutout slot 140. Where portion 200 has a notch, however, portion 100 has a semicircular cut 143.

Edges 203 and 202 are mated with portions 141 and 142, respectively, of portion 100. The latch is in its swing-out position. Rotating latch 105 back into position on housing 101 as shown in FIG. 13 turns pivot cam 133. Surface 138 of 133, which was aligned with portion 141, now turns and the otherpart of cylindrical section 137 enters the notched area on 201 and locks the members 100 and 200 together. Pivoting of latch 105 unlocks the members.

Referring to FIG. 11, there is shown the piston assembly 155 for automatically pivoting cam pivot 133 to unlock the buckle. It consists of a housing 157 which has a cylindrical bore 168 one end of which is internally threaded as at 158. A threaded plug 159 is screwed into that end of housing 157 and has a hexagonal aperture 160 in whicha tool may be inserted to turn the plug. The opposite end of 157 is counterbored as at 161 to provide a thin annular wall 162. Seated with housing 157 is a nylon no-return plug 163. A frangible shear pin 165 maintains plug 163 in place. A piston 166 is mounted beneath the plug 163 and the space between the plug 159 and piston 166 receives the flared end 167 of tubing 156 which is used to carry the gas from chamber 77 on the mechanism 70 to activate the piston assembly. When the gas acts to force piston 166 outward, it pushes against plug 163, breaking the shear pin and forcing the plug out. The plug cannot return since once the bottom edges 169 of the plug head clear the end of the housing, expansion of the nylon plug, which is force-fitted initially within housing 157 makes the diameter of the plug head portion larger than the internal diameter of the counterbored section.

As shown in FIG. 10, section 117 of the release 113 is in bore 126 and is kept there by the action of a spring 125 (FIG. 14) biasing the other end of the release upwards, thus keeping 117 in bore 126. Pressing on 113 allows 117 to move out of the hole in the direction indicated by the arrow in FIG. 10. While 113 is kept depressed the latch is swung to an unlocking position. The release 113 need not be depressed after this since 117 will stop the pivoting of 105 where it encounters bore 127 in surface 102. The action of spring 125 again forces 117 into the bore and thus locks the latch against further movement.

Pin 152 mounted on shelf 151' of area 151 anchors one end of a torsional spring 153 which extends from said pin around portion 135 of pivot cam 133 and is then anchored by a screw (not shown) or an equivalent means to pivot cam 133 which has a hole 136 for accommodating such a screw.

The spring 153 biases 133 in a direction opposite to the arrow shown adjacent 153 in FIG. 9, Le, member 153 is always abutting plug 163 of piston assembly 155. When assembly 155 is activated, plug 163 forces 153 to move, thus rotating pivot cam 133 within hole 132. Cut out area 170 is shaped so as to allow arm 153 to swing approximately 20 which is sufficient to rotate 133 to enable surface 138 of cam 133 to become flush with surface 141, thus unlocking the buckle.

OPERATION To activate the system when parachuting onto land in the absence of water one merely pulls on lanyard 97 which causes portion 94 to pull slide 90 into position to allow the cartridge 75 to be punctured by firing pin 83. The gas escapes through hole 85 in pin 83 through 78 into chamber 77 whereupon it enters a plurality of nylon tubes (not shown) which are sewn into or otherwise supported by the harness straps. The tubing carries the gas to buckles 5, 6, 7, 8 and 9. Piston assemblies such as 155 are activated and plugs such as 163 rotate pivot cams as at 133 to unlock the male and female components of the buckle to release. As the plug is held in the forward position the release is unable to reclose itself. Obviously, a safety valve may be incorporated into the system if desired.

When the foregoing occurs, all the buckles and fittings are released in unison and the harness completely divests itself from the wearer.

When landing in water, the release takes place automatically. As chutists, when landing on the water, go beneath the surface a given number of feet after impact, springs 53 are set to give under a small amount of pressure over atmospheric. As shown in FIG. 6, water enters chambers 35 in mechanism 20 through holes 40 and forces valve member 43 rearwardly compressing the springs 53. The water enters the cell 32, produces a chemical reaction generating electricity and the current passes through wires 56 to burn through the straps 10, 11 thus releasing the parachute with its shrouds from the wearer.

Simultaneously, water enters holes 40' in mechanism 20 (FIG. 7) and contacts cell 32'. The chemical reaction charges capacitor 60 which then discharges and wires 61 carry the charge to solenoid 72. Activation of solenoid 72 causes rod 72 to move thus forcing firing pin actuator slide 90 to move. This movement, in turn, allows firing pin 83 to puncture cartridge 75 and the gas is released and buckles 5, 6, 7, 8, and 9 are released in the same manner as previously described.

This procedure automatically releases the harness with its severed control straps 10 and 11 from the wearer without him having to do anything.

Obviously, only the mechanisms 13 and 14 may be used or just mechanism 70 with its mechanism It is preferred to use both systems, however.

In the water, when the automatica device 20 is submerged in water to a depth of from 2% to 3 feet, (0.085 atmospheres) water enters holes 40. When the pressure builds up to atmospheric pressure plus 0.085 atmospheres, the valves move rearwardly admitting water and exiting air from the electrolytic cell chamber. As the water comes into contact with the magnesium-silver chloride cell, it is immediately activated and begins to discharge energy into the condenser/capacitor. As soon as this is charged to 2 joules (about 4-l0 ms.) the charge is released as a bulk unit to the solenoid or to wires to burn the straps.

Usually the springs 53 are made from 0.027 in stainless steel with about 1%.. lb. extended pressure. They will respond to an added pressure of from 0.080 to 0.090 atmospheres.

The cells are standard-type magnesium-silver chloride water-activated cells. They will read with either salt or fresh water.

A discharge condenser may be placed in the circuit of mechanism 20 to insure full power.

The casings 21 of mechanisms 20 are either plastic or aluminum and can be made about three inches by one and threefourth inches by three-fourth inches. The size, therefore, is small enough not to interfere with the chutists normal range of functions while pulling on his gear or when he is wearing it.

The system is sealed by the O-rings and gaskets (not shown) to prevent accidental opening in the rain.

The cartridge may contain either carbon dioxide or nitrogen.

All internal parts are electromagnetically sealed so that static electricity or stray currents will not cause accidental operation of the device.

While several preferred embodiments of the device have been shown, it is obvious that many changes and modifications within the scope of the appended claims will be apparent to those of ordinary skill in the art.

What is claimed is:

1. An automatic releasing system for parachute harnesses comprising a housing means, a water actuatable cell contained within said housing and adapted to generate an electrical current upon contact with water, an endless high-resistance wire connected at both extremities with said water actuatable cell and adapted to be sewn into a parachute harness strap, normally closed valve means adapted to admit water to said water-actuatable cell at a predetermined liquid pressure and means adapted to secure said housing means to a harness strap whereby upon contact with water, the cell generates sufficient heat in said wires to cause them to burn and sever said harness strap.

2. A system as in claim 1 wherein said wires are microchromate wires.

3. A system as in claim 1 wherein said water-actuatable cell is a magnesium-silver chloride cell.

4. A system as in claim 1 wherein said valve means includes sealing means to prevent moisture from reaching the water-actuatable cell.

5. A system as in claim 1 wherein said valve means includes a passage means communicating between said water actuatable cell and the atmosphere, a biased valving member in a portion of said passage means and normally closing said passage means from communication with the atmosphere.

6. A system as in claim 5 wherein said valving member includes a cylindrical piston with an annular groove therein, a sealing ring in said groove adapted to cooperate with the sides of said passage means to seal said passage.

7. A system as in claim 5 including a ventilated cover member between said passage means and to atmosphere adapted to prevent accidental displacement of said biased valve member.

8. A combination automatic and manual buckle opening mechanism for a parachute harness comprising, at least one buckle having male and female components, a manually operable locking means on one of said components adapted to lock and unlock said components together, pneumatically operated means on said buckle adapted to unlock said components separate from said manually operable locking means, a housing containing pneumatic activating means including conduit means connecting it with said pneumatically operated means on said buckle, a gas release means, a water-actuatable cell adapted to automatically actuate said gas release means to pneumatically unlock said buckle components and a manually operable lever adapted to manually activate said gas release means to pneumatically unlock said buckle components.

9. A mechanism as in claim 8 wherein said male buckle component has a parallelogram-shaped projection extending therefrom, said female buckle component having an opening corresponding to the shape of the projection on the male component, one wall of said opening having a rotatable member adjacent thereto, said rotatable member having a semicircular shaped portion, the flat surface of which aligns with said wall in an unlocking position to admit said male component pro jection, said projection having a cutout portion on one side thereof which allows said rotatable member to rotate into a locking position to lock said components together, said manually operable locking means adapted to be swung to rotate said rotatable member and said pneumatically operated means adapted to rotate said rotatable member without moving said manually operable locking means, whereby upon immersion in water the water-activable cell operates said gas release means to automatically unlock said male and female components.

10. A mechanism as in claim 9 wherein said rotatable member has a radially extending lever thereon and said pneumatically operated means is positioned within said manually operable unlocking means adjacent said lever, whereby, upon manual operation, rotating of said rotatable locking member is accomplished by swinging of said manually operable means so that the pneumatically operated means engages said lever and rotates said rotatable member to unlock said components and, upon automatic operation, said pneumatically operated means is activated to swing said lever internally and independent of said manually operated means to rotate said rotatable member and unlock said components.

ILA mechanism as in claim 10 wherein said pneumatically activating means c oinprises 5 container of compressed with a frangible seal thereon and said gas release means includes a spring-biased plunger adapted to puncture said seal and allow said gas to escape through said conduit means and cause said pneumatically operated means to unlock said components.

12. A mechanism as in claim 11 wherein said gas release means further includes a slide member engagedly said manually operable lever to normally hold said plunger in retracted position, a solenoid adapted to move said slide member to release said plunger upon energization by the water-actuatable cell, and a pivot on which said manually operable lever causes said slide to move to release said plunger or said solenoid moves said slide to move also releasing said plunger.

13. A mechanism as in claim 12 wherein said housing contains a passage, said plunger positioned in said passage and having a hollow-puncturing tip, said conduit means being in open communication with said passage.

14. A mechanism as in claim 8 wherein said water-actuateble cell includes a body portion, said body portion having a normally closed valve means adapted to admit water to said cell at a predetermined liquid pressure.

15. A mechanism as in claim 14 wherein said cell is a magnesium-silver chloride cell,

16. A mechanism as in claim 14 wherein said valve means includes sealing means to prevent moisture from reaching said cell.

.17. A mechanism as in claim 14 including a ventilated cover member on said body portion covering said valve means and adapted to prevent accidental opening of said valve means.

18. In combination with a parachute harness, an automatic harness-releasing system comprising at least one housing, means securing said housing to a web of said harness, a wateractuatable cell contained within said housing and adapted to generate an electrical current upon contact with water, normally closed valve means in said housing adapted to admit water to said cell at a predetermined pressure, and at least one harness-releasing means affixed to said harness and adapted, upon energization by said cell to automatically cause said harness to release when the parachutist is immersed after a water landing.

19. A system as in claim 18 wherein said hamess-releasing means comprises at least one high-resistance endless wire, the ends of which are connected to said cell, said wire being sewn into a web on said harness whereby upon contact with water, said cell generates sufficient energy to cause said wires to heat and sever said web by burning therethrough.

20. A system as in claim 19 wherein said wire is a microchromate wire.

21. A system as in claim 19 wherein said valve means includes a sealing means to prevent moisture from reaching said cell.

22. A system as in claim 20 wherein said cell is a magnesium-silver chloride cell.

23. A system as in claim 18 wherein said harness releasing means comprises at least one buckle having male and female components a manually operable locking means on one of said components adapted to lock and unlock said components, pneumatically operated means on said buckle separate from said manually operated means adapted to unlock said components, said housing additionally containing pneumatic activating means including conduit means connecting it with said pneumatically operated means on said buckle, a gas release means, said water-actuatable cell adapted to automatically actuate said gas release means to pneumatically unlock said buckle components, said housing also containing a manually operable lever adapted to activate said gas release means to pneumatically unlock said components.

24. A system as in claim 23 wherein said pneumatically operated means comprises a no-return piston housed within a cylinder on said female component.

25. A system as in claim 23 wherein said male buckle component has a parallellogram-shaped projection extending therefrom, said female buckle component having an opening corresponding to the shape of the projection on the male component, one wall of said opening having a rotatable member adjacent thereto, said rotatable member having a semicircular shaped portion, the flat surface of which aligns with said wall in the unlocking position to admit said male component projection, said projection having a cutout portion on one side thereof which allows said rotatable member to rotate into a locking position to lock said components together, said manually operable locking means adapted to be swung to rotate said rotatable member and said pneumatically operated means adapted to rotate said rotatable member without moving said manually operable locking means, whereby upon immersion in water to a predetermined depth said water-actuateble cell operates said gas release means to automatically unlock said male and female components.

26. A system as in claim 25 wherein said rotatable member has a radially extending lever thereon, and said pneumatically operated means is positioned within said manually operated unlocking means adjacent said lever whereby upon manual operation, rotating of said rotatable unlocking member is accomplished by swinging of said manually operable means so that the pneumatically operated means engages said lever and rotates said rotatable member to unlock said components and, upon automatic operation, said pneumatically operated means is activated to swing said lever internally and independent of said manually operable means to rotate said rotatable member and unlock said components.

27. A system as in claim 26 wherein said pneumatic activating means comprises a container of compressed gas with a frangible seal thereon and said gas release means includes a spring biased plunger adapted to puncture said seal and allow gas to escape through said conduit means and cause said pneumatically operated means to unlock said components.

28. A system as in claim 27 wherein said gas release means further includes a slide member engaged by said manually operable lever to normally hold said plunger in retracted posi tion, a solenoid adapted to move said slide member to release said plunger upon energization by the water-actuatable cell.

29. A system as in claim 28 wherein said housing contains a passage, said plunger positioned within said passage and having a hollow puncturing tip, said conduit means being in open communication with said passage.

30. A system as in claim 29 wherein said pneumatically operated unlocking means comprises a cylinder located within said manually operated unlocking means and a no-return piston plug situated therein. 

1. An automatic releasing system for parachute harnesses comprising a housing means, a water actuatable cell contained within said housing and adapted to generate an electrical current upon contact with water, an endless high-resistance wire connected at both extremities with said water actuatable cell and adapted to be sewn into a parachute harness strap, normally closed valve means adapted to admit water to said wateractuatable cell at a predetermined liquid pressure and means adapted to secure said housing means to a harness strap whereby upon contact with water, the cell generates sufficient heat in said wires to cause them to burn and sever said harness strap.
 2. A system as in claim 1 wherein said wires are microchromate wires.
 3. A system as in claim 1 wherein said water-actuatable cell is a magnesium-silver chloride cell.
 4. A system as in claim 1 wherein said valve means includes sealing means to prevent moisture from reaching the water-actuatable cell.
 5. A system as in claim 1 wherein said valve means includes a passage means communicating between said water actuatable cell and the atmosphere, a biased valving member in a portion of said passage means and normally closing said passage means from communication with the atmosphere.
 6. A system as in claim 5 wherein said valving member includes a cylindrical piston with an annular groove therein, a sealing ring in said groove adapted to cooperate with the sides of said passage means to seal said passage.
 7. A system as in claim 5 including a ventilated cover member between said Passage means and to atmosphere adapted to prevent accidental displacement of said biased valve member.
 8. A combination automatic and manual buckle opening mechanism for a parachute harness comprising, at least one buckle having male and female components, a manually operable locking means on one of said components adapted to lock and unlock said components together, pneumatically operated means on said buckle adapted to unlock said components separate from said manually operable locking means, a housing containing pneumatic activating means including conduit means connecting it with said pneumatically operated means on said buckle, a gas release means, a water-actuatable cell adapted to automatically actuate said gas release means to pneumatically unlock said buckle components and a manually operable lever adapted to manually activate said gas release means to pneumatically unlock said buckle components.
 9. A mechanism as in claim 8 wherein said male buckle component has a parallelogram-shaped projection extending therefrom, said female buckle component having an opening corresponding to the shape of the projection on the male component, one wall of said opening having a rotatable member adjacent thereto, said rotatable member having a semicircular shaped portion, the flat surface of which aligns with said wall in an unlocking position to admit said male component projection, said projection having a cutout portion on one side thereof which allows said rotatable member to rotate into a locking position to lock said components together, said manually operable locking means adapted to be swung to rotate said rotatable member and said pneumatically operated means adapted to rotate said rotatable member without moving said manually operable locking means, whereby upon immersion in water the water-activable cell operates said gas release means to automatically unlock said male and female components.
 10. A mechanism as in claim 9 wherein said rotatable member has a radially extending lever thereon and said pneumatically operated means is positioned within said manually operable unlocking means adjacent said lever, whereby, upon manual operation, rotating of said rotatable locking member is accomplished by swinging of said manually operable means so that the pneumatically operated means engages said lever and rotates said rotatable member to unlock said components and, upon automatic operation, said pneumatically operated means is activated to swing said lever internally and independent of said manually operated means to rotate said rotatable member and unlock said components. 1.. A mechanism as in claim 10 wherein said pneumatically activating means comprises a container of compressed gas with a frangible seal thereon and said gas release means includes a spring-biased plunger adapted to puncture said seal and allow said gas to escape through said conduit means and cause said pneumatically operated means to unlock said components.
 12. A mechanism as in claim 11 wherein said gas release means further includes a slide member engagedly said manually operable lever to normally hold said plunger in retracted position, a solenoid adapted to move said slide member to release said plunger upon energization by the water-actuatable cell, and a pivot on which said manually operable lever causes said slide to move to release said plunger or said solenoid moves said slide to move also releasing said plunger.
 13. A mechanism as in claim 12 wherein said housing contains a passage, said plunger positioned in said passage and having a hollow-puncturing tip, said conduit means being in open communication with said passage.
 14. A mechanism as in claim 8 wherein said water-actuatable cell includes a body portion, said body portion having a normally closed valve means adapted to admit water to said cell at a predetermined liquid pressure.
 15. A mechanism as in claim 14 wherein said cell is a magnesium-silver chloride cell.
 16. A mechanism as in claim 14 wherein said valve Means includes sealing means to prevent moisture from reaching said cell.
 17. A mechanism as in claim 14 including a ventilated cover member on said body portion covering said valve means and adapted to prevent accidental opening of said valve means.
 18. In combination with a parachute harness, an automatic harness-releasing system comprising at least one housing, means securing said housing to a web of said harness, a water-actuatable cell contained within said housing and adapted to generate an electrical current upon contact with water, normally closed valve means in said housing adapted to admit water to said cell at a predetermined pressure, and at least one harness-releasing means affixed to said harness and adapted, upon energization by said cell to automatically cause said harness to release when the parachutist is immersed after a water landing.
 19. A system as in claim 18 wherein said harness-releasing means comprises at least one high-resistance endless wire, the ends of which are connected to said cell, said wire being sewn into a web on said harness whereby upon contact with water, said cell generates sufficient energy to cause said wires to heat and sever said web by burning therethrough.
 20. A system as in claim 19 wherein said wire is a microchromate wire.
 21. A system as in claim 19 wherein said valve means includes a sealing means to prevent moisture from reaching said cell.
 22. A system as in claim 20 wherein said cell is a magnesium-silver chloride cell.
 23. A system as in claim 18 wherein said harness releasing means comprises at least one buckle having male and female components a manually operable locking means on one of said components adapted to lock and unlock said components, pneumatically operated means on said buckle separate from said manually operated means adapted to unlock said components, said housing additionally containing pneumatic activating means including conduit means connecting it with said pneumatically operated means on said buckle, a gas release means, said water-actuatable cell adapted to automatically actuate said gas release means to pneumatically unlock said buckle components, said housing also containing a manually operable lever adapted to activate said gas release means to pneumatically unlock said components.
 24. A system as in claim 23 wherein said pneumatically operated means comprises a no-return piston housed within a cylinder on said female component.
 25. A system as in claim 23 wherein said male buckle component has a parallellogram-shaped projection extending therefrom, said female buckle component having an opening corresponding to the shape of the projection on the male component, one wall of said opening having a rotatable member adjacent thereto, said rotatable member having a semicircular shaped portion, the flat surface of which aligns with said wall in the unlocking position to admit said male component projection, said projection having a cutout portion on one side thereof which allows said rotatable member to rotate into a locking position to lock said components together, said manually operable locking means adapted to be swung to rotate said rotatable member and said pneumatically operated means adapted to rotate said rotatable member without moving said manually operable locking means, whereby upon immersion in water to a predetermined depth said water-actuatable cell operates said gas release means to automatically unlock said male and female components.
 26. A system as in claim 25 wherein said rotatable member has a radially extending lever thereon, and said pneumatically operated means is positioned within said manually operated unlocking means adjacent said lever whereby upon manual operation, rotating of said rotatable unlocking member is accomplished by swinging of said manually operable means so that the pneumatically operated means engages said lever and rotates said rotatable member to unlock said components and, upon automatic operation, said pneumatically oPerated means is activated to swing said lever internally and independent of said manually operable means to rotate said rotatable member and unlock said components.
 27. A system as in claim 26 wherein said pneumatic activating means comprises a container of compressed gas with a frangible seal thereon and said gas release means includes a spring biased plunger adapted to puncture said seal and allow gas to escape through said conduit means and cause said pneumatically operated means to unlock said components.
 28. A system as in claim 27 wherein said gas release means further includes a slide member engaged by said manually operable lever to normally hold said plunger in retracted position, a solenoid adapted to move said slide member to release said plunger upon energization by the water-actuatable cell.
 29. A system as in claim 28 wherein said housing contains a passage, said plunger positioned within said passage and having a hollow puncturing tip, said conduit means being in open communication with said passage.
 30. A system as in claim 29 wherein said pneumatically operated unlocking means comprises a cylinder located within said manually operated unlocking means and a no-return piston plug situated therein. 